Dover, Del. ? Tension between rival groups of friends from New Jersey and Washington, D.C., preceded the late-night shooting at Delaware State University that wounded two people, students said Saturday.

While investigators worked to find the shooter who opened fire early Friday as several students left a campus dining hall, a classmate recalled how the violence had escalated from altercations during the week.

“They’ve been getting into it, New Jersey people and D.C. people,” said James Dillion, 23, of Cleveland.

“Thursday night, they saw each other again and got into it,” he said. “Everybody’s still astonished about what happened.”

The shootings, reported to police at 12:54 a.m. Friday, occurred after a group of students left the Village Cafe dining hall and ran into another group as they walked across campus. Nathaniel Pugh, 17, was in stable condition Saturday with an ankle wound, while Shalita Middleton, also 17, was shot in the abdomen and remained in serious condition, university officials said.

Police questioned and released two students described as persons of interest. Police have not labeled either person a suspect, and no arrests have been made.

“They did provide information to us that is very useful,” campus police chief James Overton said. “It has led us to more witnesses that we are seeking now, and one other person of interest who we hope will be able to shed light on this situation.”

Investigators have not recovered a weapon or any shell casings, suggesting the gunman may have used a revolver. Witnesses reported hearing four to six gunshots.

Overton said police believe the gunman is a male Delaware State student who is no longer on campus. But he said police have not identified a suspect, and refused to clarify the apparent contradiction.

Overton said the investigation has not led police to believe there was any “turf battle.”

University President Allen Sessoms said the campus would return to normal business today, and classes would resume Monday. “We’re moving ahead,” he said.

Campus meetings were planned in response to the shooting, Sessoms said.

“Clearly, we’re doing some things well, but we need to do other things better,” he said.

Ali Muhammad, 18, a freshman from Washington, D.C., said that since the school year started he has heard of at least three fights involving cliques from New Jersey and the District of Columbia.

Earlier in the week, Muhammad said, a student from New Jersey cut the lip of a student from Washington with a key. “They said it was over a card game,” he said.